Patent Document 1 discloses a switch device which can be mounted on an instrument panel of a vehicle and on which a dial operation can be performed. The switch device has a cylindrical dial installed on the outer circumference side of a cylindrical guide member so as to be rotatable with respect to the guide member. The dial is configured by combining a cylindrical dial base, a cylindrical decorative member, and a cylindrical elastic member. On the outer circumference side of the guide member, a rotary member is mounted such that the rotary member is rotatable, and the dial base is fixed to the outer circumference of the rotary member. The decorative member is fit on the dial base. The elastic member is interposed between the outer circumference of the dial base and the inner circumference of the decorative member.
[Patent Document 1] Japanese Patent Application Laid-Open No. 2007-53061
For example, in dial type operation devices which are applied to audio systems for vehicles, abnormal noise may be produced from fitting parts and the like due to vibration of the vehicles. In the configuration of Patent Document 1, the elastic member is interposed between the dial base and the decorative member. Therefore, backlash is unlikely to occur between the dial base and the decorative member. However, in the configuration of Patent Document 1, it is required to fit the elastic member into the decorative member and fit the dial base into the elastic member. For this reason, in the case of considering workability and the like, further improvement is desired.